The world hasn't been kind to Sun for quite a while now, but with the economic downturn, things are getting worse. Sun announced today that it will be laying off 18% of its workforce, or about 6000 people. In addition, it was announced that Sun's software chief Rich Green has resigned for reasons that were not stated, although as part of Sun's reorganization and cost cutting efforts, many departments are being merged, and the software division is being restructured and reorganized.